Generated by SassMeister.com.

SassMeister-input.scss

// ----
// libsass (v3.2.5)
// ----

$sprites:
    facebook "16px 16px",
    twitter "32px 32px",
    instagram "48px 48px"
;

@each $i in $sprites {
    .icon-#{nth($i,1)}{
      background-position: #{nth($i,2)};
    }
}

SassMeister-output.css

.icon-facebook {
  background-position: 16px 16px;
}

.icon-twitter {
  background-position: 32px 32px;
}

.icon-instagram {
  background-position: 48px 48px;
}